Biodiversity
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A biome is made of many similar ecosystems. An ecosystem is often much smaller than a biome, although the size varies.
Ecosystems are the interactions between the living things and the nonliving things in a place. In an ecosystem, the plants, animals, and other organisms rely on each other and on the physical environment – the soil, water, and nutrients, for example.
Even though they are living in the same place, each species in an ecosystem has its own role to play. This role is called a niche. The niche for one species might be to climb trees and eat their fruit, while the niche for another species might be to hunt for small rodents. For a tree, a niche might be to grow tall and make food with the Sun’s energy through the process of photosynthesis. If the niche of two species is very similar, they might compete for food or other resources.
Sometimes ecosystems get out of balance. If, for example, it rains a lot and a type of bird that thrives with extra water increases in numbers, other species in the ecosystem might be crowded out. The birds might take food or space or other resources from other species. They might eat all the food. Sometimes an ecosystem naturally gets back into balance. Other times an ecosystem will become more and more out of balance. Today, human actions are having an impact on ecosystems all over the world. Making buildings and roads, fishing and farming all have an impact on ecosystems. Pollution on land, air pollution, and water pollution is sending many ecosystems out of balance too.
Tundra
Taiga
Temperate Forests
Coniferous forests
Coniferous forests are made up mainly of
cone-bearing or coniferous trees, such as spruces, hemlocks, pines and firs.
The leaves of these trees are either small and needle-like or scale-like and
most stay green all year around (evergreen). All are softwoods able to survive
cold termperatures and acidic soil.
Coniferous forests are found mainly in the
northern hemisphere, although some are found in the southern hemisphere.
The northern coniferous forests are called taiga or boreal forests. They cover vast areas of North America from the Pacific to the Atlantic, and range across northern Europe, Scandinavia, Russia and across Asia through Siberia and Mongolia to northern China and northern Japan.
Short summers and long winters
Coniferous trees thrive where summers are short and cool and winters long and harsh, with heavy snowfall that can last as long as 6 months. The needle-like leaves have a waxy outer coat which prevents water loss in freezing weather and the branches are soft and flexible and usually point downwards, so that snow slides off them. Larches are one example of a coniferous tree found in some of the coldest regions. Unusually for coniferous trees they are deciduous, that is they shed their leaves in winter.
Coniferous trees such as cypresses, cedars and redwoods are found in warmer regions.
Life on the forest floor
Even evergreen trees eventually shed their leaves and grow new ones. The needles fall to the forest floor and form a thick springy mat. Thread-like fungi help to break down or decompose the fallen needles. These fungi provide nutrients from the decomposed needles back to the roots of the trees. But because pine needles do not decompose easily, the soils are poor and acid.
These forests grow under widely differing conditions of climate and soil - from the tropics to the subarctic, and from heavy clays to poor sands. However, coniferous trees are especially conditioned to the winter climate. The trees of the taiga grow at the highest latitude of any forest. The most common are spruce, pine and firs.
Reach for the sky!
Cypresses, cedars and redwoods grow upright; the tallest of them can reach 20m in height. The trees are usually pyramid-shaped. Short, lateral branches grow quite close together but they are so flexible that the snow simply slides off. The leaves are small, hard and evergreen.
Little light penetrates the thick canopy of trees to reach the forest floor. Because of this gloom, only ferns and a few herbaceous plants grow here. Mosses, liverworts and lichens are also found on the forest floor and grow on tree trunks and branches. There are few flowering plants.
The northern coniferous forests are called taiga or boreal forests. They cover vast areas of North America from the Pacific to the Atlantic, and range across northern Europe, Scandinavia, Russia and across Asia through Siberia and Mongolia to northern China and northern Japan.
Short summers and long winters
Coniferous trees thrive where summers are short and cool and winters long and harsh, with heavy snowfall that can last as long as 6 months. The needle-like leaves have a waxy outer coat which prevents water loss in freezing weather and the branches are soft and flexible and usually point downwards, so that snow slides off them. Larches are one example of a coniferous tree found in some of the coldest regions. Unusually for coniferous trees they are deciduous, that is they shed their leaves in winter.
Coniferous trees such as cypresses, cedars and redwoods are found in warmer regions.
Life on the forest floor
Even evergreen trees eventually shed their leaves and grow new ones. The needles fall to the forest floor and form a thick springy mat. Thread-like fungi help to break down or decompose the fallen needles. These fungi provide nutrients from the decomposed needles back to the roots of the trees. But because pine needles do not decompose easily, the soils are poor and acid.
These forests grow under widely differing conditions of climate and soil - from the tropics to the subarctic, and from heavy clays to poor sands. However, coniferous trees are especially conditioned to the winter climate. The trees of the taiga grow at the highest latitude of any forest. The most common are spruce, pine and firs.
Reach for the sky!
Cypresses, cedars and redwoods grow upright; the tallest of them can reach 20m in height. The trees are usually pyramid-shaped. Short, lateral branches grow quite close together but they are so flexible that the snow simply slides off. The leaves are small, hard and evergreen.
Little light penetrates the thick canopy of trees to reach the forest floor. Because of this gloom, only ferns and a few herbaceous plants grow here. Mosses, liverworts and lichens are also found on the forest floor and grow on tree trunks and branches. There are few flowering plants.
Tropical Rainforests
The Desert
Grasslands
The
Savanna
A savanna is a rolling grassland scattered with shrubs and isolated
trees, which can be found between a tropical rainforest and desert biome. Not
enough rain falls on a savanna to support forests. Savannas are also known as
tropical grasslands. They are found in a wide band on either side of the
equator on the edges of tropical rainforests.
Savannas have warm temperature year round. There are actually two very
different seasons in a savanna; a very long dry season (winter), and a very wet
season (summer). In the dry season only an average of about 4 inches of rain
falls. Between December and February no rain will fall at all. Oddly enough, it
is actually a little cooler during this dry season. But don't expect sweater
weather; it is still around 70° F.
In the summer there is lots of rain. In Africa the monsoon rains begin
in May. An average of 15 to 25 inches of rain falls during this time. It gets
hot and very humid during the rainy season. Every day the hot, humid air rises
off the ground and collides with cooler air above and turns into rain. In the
afternoons on the summer savanna the rains pour down for hours. African
savannas have large herds of grazing and browsing hoofed animals. Each animal
has a specialized eating habit that reduces compitition for food.
There are several different types of savannas around the world. The
savannas we are most familiar with are the East African savannas covered with
acacia trees. The Serengeti Plains of Tanzania are some of the most well known.
Here animals like lions, zebras, elephants, and giraffes and many types of
ungulates(animals with hooves) graze and hunt. Many large grass-eating mammals
(herbivores) can survive here because they can move around and eat the
plentiful grasses. There are also lots of carnivores (meat eaters) who eat them
in turn.
South America also has savannas, but there are very few species that
exist only on this savanna. In Brazil, Colombia, and Venezuela, savannas occupy
some 2.5 million square kilometers, an area about one-quarter the size of
Canada. Animals from the neighboring biomes kind of spill into this savanna.
The Llanos of the Orinoco basin of Venezuela and Columbia is flooded annually
by the Orinoco River. Plants have adapted to growing for long periods in
standing water. The capybara and marsh deer have adapted themselves to a
semi-aquatic life.
Brazil's cerrado is an open woodland of short twisted trees. The
diversity of animals is very great here, with several plants and animals that
don't exist anywhere else on earth.
There is also a savanna in northern Australia. Eucalyptus trees take the
place of acacias in the Australian savanna. There are many species of kangaroos
in this savanna but not too much diversity of different animals
Plants of the savannas are highly specialized to grow in this
environment of long periods of drought. They have long tap roots that can reach
the deep water table, thick bark to resist annual fires, trunks that can store
water, and leaves that drop of during the winter to conserve water. The grasses
have adaptations that discourage animals from grazing on them; some grasses are
too sharp or bitter tasting for some animals, but not others, to eat. The side
benefit of this is that every species of animal has something to eat. Different
species will also eat different parts of the grass. Many grasses grow from the
bottom up, so that the growth tissue doesn't get damaged by grazers. Many
plants of the savanna also have storage organs like bulbs and corms for making
it though the dry season.
Most of the animals on the savanna have long legs or wings to be able to
go on long migrations. Many burrow under ground to avoid the heat or raise
their young. The savanna is a perfect place for birds of prey like hawks and
buzzards. The wide, open plain provides them with a clear view of their prey,
hot air updrafts keep them soaring, and there is the occasional tree to rest on
or nest in. Animals don't sweat to lose body heat, so they lose it through
panting or through large areas of exposed skin, or ears, like those of the
elephant.
The savanna has a large range of highly specialized plants and animals.
They all depend on the each other to keep the environment in balance. There are
over 40 different species of hoofed mammals that live on the savannas of
Africa. Up to 16 different species of browsers (those who eat leaves of trees)
and grazers can coexist in one area. They do this by having their own food
preferences, browsing/grazing at different heights, time of day or year to use
a given area, and different places to go during the dry season.
These different herbivores provide a wide range of food for carnivores,
like lions, leopards, cheetahs, jackals and hyenas. Each species has its own
preference, making it possible to live side by side and not be in competition
for food.
In many parts of the savannas of Africa people have started using it to
graze their cattle and goats. They don't move around and soon the grasses are
completely eaten up. With no vegetation, the savanna turns into a desert. Huge
areas of savanna are lost to the Sahara desert every year because of
overgrazing and farming.
Definition of Biodiversity:
Biodiversity has been most generally defined as the "full variety of life on Earth". More specifically, biodiversity is the study of the processes that create and maintain variation. It is concerned with the variety of individuals within populations, the diversity of species within communities, and the range of ecological roles within ecosystems.
Importance of biodiversity
Environmental problems : Earth functions like a complex system with very complex components that affect each other. Each species -- from the lowliest microbe to humans -- plays a part in keeping the planet running smoothly. In this sense, each part is related. If a lot of those parts suddenly vanish, then the machine that is Earth can't function properly.
For example, the crops that we grow though our clever use of agriculture are enabled by the nitrogen present in the soil. This nitrogen nourishes and strengthens our crops. But where does it come from? Worms, bacteria and other life found within the soil love to decompose vegetation. When they eat, these organisms produce nitrogen as waste. This nitrogen is used to make soil rich.
If we have a small bottle with a group of dominating predators and prey together, soon they will both die out because there is no sustainability. Likewise, if humans manipulate the environment and decrease biodiversity, our environmental sustainability significantly decreases.
Economic Importance of Biodiversity:
• Biologically diverse ecosystems are typically more productive than non-diverse ones because they contain a wider array of resources, and it is impossible for us to use up all of them at once.
• Biodiversity provides many different resources that can be exploited economically, such as fibres wood, fuels, rubber, and silk.
• Many medicines are made from extracts taken from the Amazon rainforest
• Biodiverse environments can often be used as tourist attractions
• The Amazon rainforest is one of the most dominant rubber-producers in the world
• Illegal biological trade exploiting wildlife
• Wood industry
• payments for ecological services rendered by the Amazon such as the carbon retaining in its forests could go a long way to preserving them, a new study has found.
Biodiversity has been most generally defined as the "full variety of life on Earth". More specifically, biodiversity is the study of the processes that create and maintain variation. It is concerned with the variety of individuals within populations, the diversity of species within communities, and the range of ecological roles within ecosystems.
Importance of biodiversity
Environmental problems : Earth functions like a complex system with very complex components that affect each other. Each species -- from the lowliest microbe to humans -- plays a part in keeping the planet running smoothly. In this sense, each part is related. If a lot of those parts suddenly vanish, then the machine that is Earth can't function properly.
For example, the crops that we grow though our clever use of agriculture are enabled by the nitrogen present in the soil. This nitrogen nourishes and strengthens our crops. But where does it come from? Worms, bacteria and other life found within the soil love to decompose vegetation. When they eat, these organisms produce nitrogen as waste. This nitrogen is used to make soil rich.
If we have a small bottle with a group of dominating predators and prey together, soon they will both die out because there is no sustainability. Likewise, if humans manipulate the environment and decrease biodiversity, our environmental sustainability significantly decreases.
Economic Importance of Biodiversity:
• Biologically diverse ecosystems are typically more productive than non-diverse ones because they contain a wider array of resources, and it is impossible for us to use up all of them at once.
• Biodiversity provides many different resources that can be exploited economically, such as fibres wood, fuels, rubber, and silk.
• Many medicines are made from extracts taken from the Amazon rainforest
• Biodiverse environments can often be used as tourist attractions
• The Amazon rainforest is one of the most dominant rubber-producers in the world
• Illegal biological trade exploiting wildlife
• Wood industry
• payments for ecological services rendered by the Amazon such as the carbon retaining in its forests could go a long way to preserving them, a new study has found.
Geographic Conditions that Favor Biodiversity
According to how geographical natural components are
combined, different sceneries are created for the development of species;
depending on the combination of features biodiversity is distributed in our
planet.
Biodiversity is a result of the evolution of life
through millions of years, due to geological processes, as the formation and
arrangement of continents, climate changes, ice age, and evolution of species.
There are around 30 million of different species in the world. Some of the
geographical conditions that favor biodiversity in the world are:
Geographic
location
The inter tropical zone (between the tropics of Cancer
and Capricorn) is the one that as the biggest amount of species because warm
stripes due to latitude are good conditions for different species that can
adapt to live in high temperatures and lots of humidity.
Continentality
Having oceans and seas contributes for a broadest
biodiversity in a country. These bodies of water and the ocean currents have
influence in climate, which favors diversity of vegetal and animal species.
Diversity of
Landscape
It is the result of the combination of unique natural
components, as well as climates with specific relief and native vegetation.
Isolation
The separation of islands and continents, together
with specific natural characteristics of a region as well as its relief
hydrology, climate and vegetation, has allowed the development of unique
species, called endemic, because they can´t be found in any other place on the
planet.
Megadiverse Countries
The megadiverse countries are a group of countries
that harbor the majority of the Earth's species and are therefore considered
extremely biodiverse. Conservation International identified 17 megadiverse
countries in 1998.[1][2][3] All are located in, or partially in, the tropics.
In 2002, Mexico formed a separate organization
focusing on Like-Minded Megadiverse Countries, consisting of countries rich in
biological diversity and associated traditional knowledge. This organization
does not include all the megadiverse countries as identified by Conservation
International.
Megadiverse countries
In alphabetical order, the 17 countries are:
Australia
Brazil
China
Colombia
Democratic Republic of the Congo
Ecuador
India
Indonesia
Madagascar
Malaysia
Mexico
Papua New Guinea
Peru
Philippines
South Africa
United States